Lead attachment for electroluminescent lamp

Abstract

An electroluminescent sheet-form lamp comprising a transparent insulation layer, a transparent first conductive layer below the insulation layer forming a first electrode, a layer of phosphor material below the first conductive layer, a layer of dielectric material below the phosphor layer, a second conductive layer below the dielectric layer forming a second electrode, and electrical connection means for applying an electrical potential between the conductive layers to cause the phosphor to transmit light through the transparent conductive layer and the transparent insulation layer, one of the conductive layers having been formed as a general conductive coating preapplied over a panel of larger dimension than the lamp, from which the lamp has been cut. The lamp provides an improved electrical connection, wherein the one conductive layer has a line of interruption which isolates a localized region of the one conductive layer from electrical continuity with a main portion of the one conductive layer, the main portion of the one conductive layer forming the respective electrode and being connected to one of the connection means to apply electrical potential thereto without applying electrical potential to the localized region, the connection means for the other of the conductive layers which forms the other of the electrodes being located in coincidence with the area of the localized region, one of the connection means employing deformation of the sheet-form lamp, whereby the electrical isolation of the localized region prevents electrical shorting between the conductive layers as a result of the deformation.

We claim: 
     
       1. In an electroluminescent sheet-form lamp comprising a transparent insulation layer, a transparent first conductive layer below said insulation layer forming a first electrode, a layer of phosphor material below said first conductive layer, a layer of dielectric material below said phosphor layer, a second conductive layer below said dielectric layer forming a second electrode, and first and second electrical connection means for applying an electrical potential between the conductive layers to cause the phosphor to transmit light through the transparent conductive layer and said transparent insulation layer, one of said conductive layers having been formed as a general conductive coating preapplied over a panel of larger dimension than said lamp, from which said lamp has been cut, the improvement providing improved electrical connection, wherein said one of said conductive layers has a line of interruption which isolates a localized region of said one of said conductive layers from electrical continuity with a main portion of said one of said conductive layers, said localized region and said main portion comprising in aggregate said one of said conductive layers, said main portion of said one of said conductive layers forming the respective electrode and being connected to said first connection means to apply electrical potential thereto without applying electrical potential to said localized region, the second connection means for the other of said conductive layers which forms the other of said electrodes being located in coincidence with the area of said localized region, said second connection means resulting in deformation of the sheet-form lamp,   whereby the electrical isolation of said localized region prevents electrical shorting between said conductive layers as a result of said deformation.   
     
     
       2. The electroluminescent lamp of claim 1 further comprising a second insulation layer below said second conductive layer. 
     
     
       3. The electroluminescent lamp of claim 2 wherein one of said insulation layers forms a substrate upon which subsequent layers of said lamp are applied. 
     
     
       4. The electroluminescent lamp of claim 1 wherein said one of said conductive layers is said first conductive layer and said other of said conductive layers is said second conductive layer. 
     
     
       5. The electroluminescent lamp of claim 1 wherein said one of said conductive layers is said second conductive layer and said other of said conductive layers is said first conductive layer. 
     
     
       6. In an electroluminescent sheet-form lamp comprising a transparent substrate layer, a transparent first conductive layer over said substrate layer forming a first electrode, a layer of phosphor material over said first conductive layer, a layer of dielectric material below said phosphor layer, a second conductive layer below said dielectric layer forming a second electrode, and first and second connection means associated with respective conductive layers for applying an electrical potential between said electrodes to cause the phosphor to transmit light through the transparent first conductive layer and the transparent substrate, said first transparent conductive layer having been formed as a general conductive coating preapplied over a panel of said substrate layer of larger dimension than said lamp, the improvement providing improved electrical connection, wherein said first conductive layers has a line of interruption which isolates a localized region of said first conductive layer from electrical continuity with a main portion of said first conductive layer, said main portion of said first conductive layer forming said first electrode and being connected to said first connection means to apply electrical potential thereto without applying electrical potential to said localized region, the second connection means for said second conductive layer that forms said second electrode being located in coincidence with the area of said localized region, said second connection means employing deformation of the sheet-form lamp,   whereby the electrical isolation of said localized region prevents electrical shorting between said conductive layers as a result of said deformation.   
     
     
       7. The electroluminescent lamp of claim 1 or 6 wherein connection of said second connection means to its respective conductive layer is formed by compression of the thickness of the sheet-form member. 
     
     
       8. The electroluminescent lamp of claim 7 wherein said connection is formed by crimping said second connection means onto said sheet-form member. 
     
     
       9. The electroluminescent lamp of claim 1 or 6 wherein said second connection means comprises an eyelet clamped on said sheet-form member at an opening through its thickness. 
     
     
       10. The electroluminescent lamp of claim 1 or 6 wherein said second connection means comprises a thickness-penetrating member such as a conductive pin or stake. 
     
     
       11. The electroluminescent lamp of claim 1 or 6 wherein said second connection mans attaches to said first and second electrodes by piercing said conductive layers. 
     
     
       12. The electroluminescent lamp of claim 1 or 6 wherein said line f interruption begins at an outer edge of a respective one of said conductive layers, extends away from said outer edge into the interior of said conductive layer, and turns back to said outer edge in the manner to extend about and isolate said localized region at the edge of said respective conductive layer. 
     
     
       13. The electroluminescent lamp of claim 1 or 6 wherein said line of interruption is disposed inwardly from all edges of a respective one of said conductive layers, said line of interruption being closed upon itself to define said localized region as an island within the perimeter of said respective conductive layer. 
     
     
       14. The electroluminescent lamp of claim 1 or 6 wherein said line of interruption forming said localized region is a laser scribed line. 
     
     
       15. The electroluminescent lamp of claim 6 wherein an insulation layer is provided over said second conductive layer. 
     
     
       16. The electroluminescent lamp of claim 1 or 6, said lamp further comprising an edge region susceptible to formation of a detrimental, electrically conductive path, wherein the main portion of a respective one of said conductive layers is isolated from the susceptible edge region by isolation provided along at least a portion of the perimeter of the lamp as a result of removal of said preapplied conductive coating such that, at the edge region of said isolation, said main portion of said one of said conductive layers which forms the respective electrode commences at a line spaced inwardly from the outer edge of said lamp, said electrical connection for the respective conductive layer being made to said main portion and being electrically isolated from said susceptible edge region, whereby a lamp formed by cutting its outline from said panel of larger dimension provides a lamp for which the formation of said conductive path in said edge region does not cause an adverse effect.   
     
     
       17. The electroluminescent lamp of claim 16 wherein said preapplied conductive coating material has been removed to from a line of interruption that leaves in place a narrow margin of conductive coating in said edge region which is electrically isolated from the main portion of the coating forming the first electrode. 
     
     
       18. In an electroluminescent sheet-form lamp comprising, in successive relationship, a rear substrate layer, a preapplied conductive layer over said substrate layer forming a back electrode, a layer of dielectric material over said preapplied conductive layer, a layer of phosphor material over said dielectric layer, a transparent conductive layer applied over said phosphor layer forming a transparent electrode, and electrical connection means associated with respective conductive layers for applying an electrical potential between the conductive layers to cause the phosphor to transmit light through the transparent conductive layer, the improvement providing improved electrical connection, wherein said preapplied conductive layer that forms said back electrode has a line of interruption which isolates a localized region of said preapplied conductive layer from electrical continuity with a main portion of said preapplied conductive layer, said main portion of said preapplied conductive layer forming the rear electrode and being connected to a first one of said connection means to apply electrical potential thereto without applying electrical potential to said localized region, a second one of the connection means for said transparent conductive layer which forms said transparent electrode being located in coincidence with the are of said localized region, said second one of the connection means employing deformation of the thickness of the sheet-form lamp,   whereby the electrical isolation of said localized region prevents electrical shorting between said conductive layers as a result of said deformation.   
     
     
       19. The electroluminescent lamp of claim 18 wherein connection of said second one of the connection means to said conductive layers is formed by compression of the thickness of the sheet-form member. 
     
     
       20. A method of providing improved electrical connection to an electroluminescent lamp, comprising providing an electroluminescent sheet-form lamp member comprising a transparent substrate layer, a transparent first conductive layer over said substrate layer forming a first electrode, a layer of phosphor material over said first electrode layer, a layer of dielectric material over said phosphor layer, a second conductive layer over said dielectric layer forming a second electrode, and first and second connection means to the respective electrode layers for applying an electrical potential between the electrode layers to cause the phosphor to transmit light through the transparent first electrode layer and the transparent substrate, one of said conductive layers having been formed as a general conductive coating preapplied over a panel of said substrate layer of larger dimension than said lamp,   including providing in said one of said conductive layers, a line of interruption which isolates a localized region of said one of said conductive layers from electrical continuity with a main portion of said one of said conductive layers, said localized region and said main portion comprising in aggregate said one of said conductive layers, said main portion of said one conductive layer forming the respective electrode and having a connection made therewith to apply electrical potential thereto without applying electrical potential to said localized region, and making the connection for the other of said conductive layers which forms the other electrode in a location coincident with the area of said localized region, said connection means employing deformation of the sheet-form lamp, the electrical isolation of said localized region preventing electrical shorting between said conductive layers as a result of said deformation.   
     
     
       21. A method of providing improved electrical connection to an electroluminescent lamp, comprising providing, in successive relationship, a rear substrate layer, a preapplied conductive layer over said substrate layer forming a back electrode, a layer of dielectric material over said preapplied conductive layer, a layer of phosphor material over said dielectric layer, a transparent conductive layer applied over said phosphor layer forming a transparent electrode, and electrical connection means for applying an electrical potential between the conductive layers to cause the phosphor to transmit light through the transparent electrode, one of said conductive layers having been formed as a general conductive coating preapplied over a panel of said substrate layer of larger dimension than said lamp,   including providing in said one of said conductive layers, a line of interruption which isolates a localized region of said one of said conductive layers from electrical continuity with a main portion of said one of said conductive layers, said localized region and said main portion comprising in aggregate said one of said conductive layers, said main portion of said one conductive layer forming the respective electrode and having a connection made therewith to apply electrical potential thereto without applying electrical potential to said localized region, and making the connection for the other of said conductive layers which forms the other electrode in a location coincident with the area of said localized region, said connection means employing deformation of the sheet-form lamp, the electrical isolation of said localized region preventing electrical shorting between said conductive layers as a result of said deformation.